Excretion and metabolism of zoniporide were investigated in humans after intravenous infusion of [(14)C]zoniporide at an 80-mg dose. Bile was the primary route of excretion because 57% of dose was recovered in the feces after intravenous infusion. Zoniporide was primarily cleared via metabolism in humans. 2-Oxozoniporide (M1) was the major excretory and circulating metabolite in humans and was catalyzed by aldehyde oxidase (K(m) of 3.4 microM and V(max) of 74 pmol/min/mg protein). Metabolites… CONTINUE READING